Drawing-press.



8.1. LINDGREN.

4 SHEETSSHEET 1- Fig.1.

Patented June 4, 1918.-

B. J. LINDGREN.

DRAWING PRESS.

APPLICATION FILED MAR. 7. 1917.

Patented June 4, 1918.

' IN VEN TUH B. J. LINDGREN.

DRAWING PRESS.

APPLICATION F,ILED MAR. 7. 1917.

1 268;37@ I I Patented June 4, 1918 4 SHEETS-SHEET 3.

8.1. LINDGREN.

' DRAWING PRESS.

APPLICATION FILED MAR. I, 1911.

Patented June 4, 1918 4SHEETS-SHEET 4.

(A L-L BLANK HOLDER LOWERED DIG RAIQEI'I m nwzgun U DLANM nuns: 5 5

ent No. 1,013,902, dated Januar ED TAT PATIENT FFEC.

BROR J. LINDGREN, OF TOLEDO, OHIO, ASSIGNOR TO THE TOLEDO MACHINE & TOOL COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO.

DRAWING-PRESS.

Application filed March 7, 1917. Serial No. 153,099.

To all whom it may concern.-

Be it known that I, Bron J. LINDGREN, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have invented a certain new and useful Drawing-Press; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

This invention relates to drawing presses of the type in which the blank-holder and drawing die are operated from a, common crank-shaft and the blank-holder'is caused to dwell in holding contact with the work blank during the work shaping movement of the 'drawingdie.

The object of my invention is to improve on the blank-holder controlling means shown and described in United States Letters Pat- 9, 1912, whereby a balanced action is e ected between the blank-holder and die moving mechanisms, a less strain is exertedv on certain of the blank-holder controlling mechanism studs, and a more perfect dwell of the blank-holder and controlling parts effected. Other objects and advantages of the invention will be apparent from the following detailed description thereof.

While the invention, in its broader aspect, is capable of embodiment in numerous forms, a preferred embodiment thereof is illustrated in the accompanying drawings,

in which Figures 1 and 2 are front and side elevat1ons, respectively, of a press embodying my invention, with the blank-holder and drawing die in lowered' position. Fig. 3 is a cross-section on the line 33 in Fig. 1. Fig. 4 is a partial side elevation of the press with blank-holder and drawing die raised, and Fig. 5 is a diagram of the relative movement of the different press mechanisms.

Referring to the drawings,'l designates the body or frame of the press; 2 the lower or matrix die; 3 the blank-holder; 4 the press-plunger, which is guided for vertical movements in the blank-holder and carries a drawing die suitable to the matrix; 5 the means is connected. This crank-arm main driving shaft, which maybe geared or otherwise connected to any suitable source of power; 6 an inner crank on the driving shaft, which is operatively connected to the press-plunger, and 7 a crank-arm located without the frame on the end of the driving shaft opposite to that to which the driving projects from the opposite side of the shaft 5 to the crank 6 but is not, in the present instance, in direct diametrically opposed relation thereto with respect'to the shaft axis.

Parallel rock-shafts 8, 8 are mounted in the upper portion ofv the frame 1 at opposite sides of the driving shaft and eachrockshaft has two pairs of outwardly projecting rocker-arms 9 disposed in a common plane between the frame'sides and to the free ends of which arms are pivoted links 10, which are connected at their lower ends to the blank-holder 3, whereby a rocking of the shafts 8, 8 will impart vertical reciprocatory movements to the blank-holder, as well understood in the art.

ward at equal angles of, in the present instance, approximately 125 from the rockerarms 9 of the respective rock-shafts, whereby to cooperate with said arms and shafts to form bell-crank or angled levers. To the Patented June a, rate.

outer rocker-arms '11, 11, which extend in y free end of each rockerarm 11 is pivoted I the upper end of a' link or connecting bar 12, the lower end of which is pivoted to the upper end of a' rockerarm l3, which-pivotally rises from a bearing stud 14 adjacent the respective edge of the frame side. When the blank-holder 3 is in lowered or blankholding position the toggles formed by the connected rocker-arms 9 and links 10 are disposed in straight or longitudinally alined position and the connected links 12 and rocker-arms 13 also stand in straightened or ipngitudinally alined position, as shown in A block 15 is mounted for vertical reciprocatory movements below the crank-arm 7 in suitable guides 16 provided on the respective frame side, and this block is connected by a pitman or connecting rod 17 to said crank-arm. A link 18 pivotally projects from the upper end of the block 15 adjaotally connected to cent to each side edge thereof and is pivthe adjacent rockerarm 13 at a point between its axis and the point of connection of the link 12 thereto, as shown in Figs. 2 and 4.

By reference to the diagram, Fig. 5, and also by reference to Figs. 2' and .4, it will be noted-that in the operation of my improved machine the block 15 is at the limit of its upward stroke when the blank-holder 3 is at'dwell in its lowered blank-holding position and the press-plunger 4 is in lowered position, thereby causing a balanced action on the shaft 5'betweenthe control mechanism for the blank-holder and thecontrol means for the press-plunger. The importance of this balanced action will be apparent to persons skilled in the art. It is also evident from the diagram that the period of dwell of the blank-holder takes place when the crank 7 is at the upper portion of its throw and moving approximately between the points a-b, and-that the distance of movement c-d of the. slide-block 15 during such period of dwell is materially less than the distance of movement 0d of the slide-block,,which would take place if the crank 7 were at the lower portion of its throw, moving approximately between the points e-.f, during the dwell period. It has also been demonstrated in practice that the positioning of the connection between the slide-block and rocker-arms 13 above the studs 14 instead of below the same, as

. prolongs the life thereof, as well has heretofore been the case, very materially diminishes the strain on the studs 14 and breakage and strain on the rocker-arms 13.

I-wish it understood thatmy invention is not limited to any specific construction, arrangement or form of the parts, except in so far as such limitations are specified in the claims.

Having thus described my invention, what I claim as new, and desire to secureby Letters Patent, is,-

1. In a drawing'press, a frame, a slideblock, a blank-holder and plunger mounted for relative parallel reciprocatory "movements in said frame, a main crank-shaft in said frame, separate means connecting said crank-shaft and said block and plunger to impart opposed reciprocatory movements thereto from a rotation of the shaft, a double armed lever fulcrumed in said frame for vertical rocking movements, connection between one arm of said lever and the blank-holder, a rocker-arm carried by the frame at one side of the slideblock, a link connecting the free end of said rocker-arm and the other arm of said lever,

as lessens v a die-carrying and a link connecting said slide-block and rocker-arm and pivoted to the latter between its axis and free end.

. 2; In a drawing-press, a frame, a slideblock, a blank-holder and a die-carrying plunger mounted for relative parallel reciprocatory movements in said frame, a drive-shaft in said frame, separate means connecting said slide-block and plunger to said shaft to impart opposed reciprocatory movements thereto when the shaft isrotated, a rocker-arm pivoted to the frame at a side of said block, a link pivotally extending from said block and pivoted to said rocker-arm between its axis and free end, and a link and lever connectionbetween the free end of the rocker-arm and the blankholder to cooperate with said link and arm to impart predetermined movements to the blank-holder from movements of, the slideblock.

3. In a-drawing press, a frame, a slideblock, a blank-holder and a ,die-carrying plunger mounted for relative parallel reciprocatory movements in said frame, drive means connected to said block and plunger and operable to impart opposed reciproca-' tory movements in unison thereto, a rockerarm pivoted to the frame at each side of said block for vertical rocking movements, a link connection between said rocker-arm intermediate its ends and said block, and link and lever connection between the free end of said rocker-arm and'the blank-holder for cooperating with said link connection and arm to communicate downward movements to the blank-holder from upward movements of the slide-block and vice versa.

4. In a drawing press, a frame, a slideblock, a blank-holder and a die-carrying plunger mounted for relative parallel reciprocatory movements in said frame, a crankshaft mounted in said frame, means con necting said shaft and both said slideblock and 5 plunger for imparting predetermined reciprocation thereto from a rotation of said shaft, rocker-arms mounted for vertical rocking movements at opposite sides of .said block, link connection between each BROR J. LINDGREN d 

